Steve Martin says he was left "flabbergasted" after working with Paul McCartney on his recent solo album.Steve Martin, the American comedian who released his new bluegrass album 'Rare Bird Alert' yesterday (15th March 2011) has spoken of the pride he felt after working with Beatles legend Paul Mccartney, reports the Associated Press.The comedian says he still remains surprised that MCCartney agreed to the collaboration, saying, "It's very hard to believe. I was a kid when I first heard Paul MCCartney, and if you told me one day that he'd be singing one of my tunes... I'm still flabbergasted". The former Beatle added vocals on the track 'Best Love' and country trio Dixie Chicks also feature on the record, as do The Steep Canyon Rangers. The comedian is a long-time banjo player and his debut album 'The Crow: New Songs for the 5-String Banjo' hit the top spot in the US bluegrass charts in the 2009. The 65-year-old also scooped the Grammy Award for 'Best Bluegrass Album' in 2010.Despite his foray into the music world, Steve Martin is set to appear in the highly-anticipated comedy movie 'The Big Year', due for release late this year. The film follows the story of three avid birdwatchers who compete to spot the rarest breeds in North America.